Selector-switch.



M K. McGRATH. SELECTOR SWITCH.

APPLICATION FILED JUNE 12} 1916.

1,251,795. I Patented Jan. 1,1918.

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- 30 bnushvsupporting member of theswitch.

UNITED PATENT (D -FFICE.

inq mminr, raw 103K. 1 .e smnon o .WESTERN-ELEGTBIQGQM- gram, .msqsrnnettn, ,Q .NEW roa s N AKGQBPQBATIQN or NEW- 201 SELECTOR-SWITCH.

Za all/w homit may -mnce1m {Be it :known "that I,.:-MAU,R10E K. -=Mo- Guru, :1 oitizemoi-the: United States, residing at New York, the county of \New York andState of New York, l1a ve. invented certain new ,and' useful "Improvements .'.in SelectonSyyitches, .'.of (which the following .isa-zfull, clear, concise and exact descrip tio (This invention .relates to. electrically-operated switchingzdeuices for use in automatic telephone systems.

' One object. of the? invention; is; to obtai a all-switching device in iwhichabrush carriage is -capable of moying at high speed over large groups of contacts, and where brakingaction i applied; to the abrush carriage; to stop the same gradually under all conditions thus admitting of.- the brush carriage being of heavier. and more robust constructi0n',;.since. itstdesign is not" limited by con siderationof rapid acceleration and retardation, which are usually controlling "factors in the. design .of switches intended to be actuated by. rapid impulses of current.

"A further objectof the invention is the provision .of switching control means in Which alight and readily movable stop mem ber may bemoved; to a desired position during the continuous movement of the heavier 'Anotherihbjecttis .to-efiect the utilization ofi the mass of/movahlenparts to aidand acoeleratethe mouement .ofrthe switch in reach ing; the.- "desired position.

Additional; objects are to oflect common operation/inf the parts of the switch structurepaiid tosefiectithe-resetting of the deuice to; norm alzthrough actuation of a single partiof theadevjce.

Still other. -.obj ects are to efiect the positivelocfing of. the stop mechanism; against overthrow to-efi'ect. a igradualstopping of the; mechanism,gtlulsobviating thejar attends-ntto aquickzstapping ;-andto effect the balanced-operation ofthe stop-setting means.

{In ;,;a step-byestep operated switch, the speed with which the brush-supporting membersmaylbemoyedxis limitedby the-mass of th iblfilshu afadgwitsl movable support, owing to Y the .immperatively greats-inertia I of the moved qne-mber. In thepresent invention, a light and aneadily grotatahle step is unloved ,Specifleation of Letters Patent.

.P ente Jan...1,=.1.91

Applicaflonfiled June 12, 1916. Serial No. 103.228.

switching device is caused .to ffollowsaid stop ina continuous movement, thereby per niittinga much more rapid operation of. the switch. 1

When a switch istaken for use, an auxiliary switch is operated torelease the holding means for the brush-support. .The. support then moves at highspeed .to its proper group position, under control of the stop-setting memberin accordance with thedigit impulses sent by thesubscriber. The auxiliarycswitch acts aiterlthe group has been selected to associate the holding meansewith the switch bar and to disengage the stop-settingstepping members. If the switch is employed as a final switch, impulses corresponding; to, the units arev thensent to step the switch bar at a. slower. speed to engage the .brushes with the desired line.

:Referring tothe drawings, Figure 1 is .a side-elevation, partly in section of the operating mechanism formingv the subject of, the present invention; Fig. 2is. a cr0ss-section on the line 2-2 of Fig. 1 Fig. 3 is a crosssection .on. the line 33v of'Fig. 1;;Fig.=:4 is a; cross-section illustrating the manner of joining the stop. member to the gearnwheel, which is moved by the brush-supporting ele ment; Fig. 5 is a cross-section on the line ofFig..4;,and Fig.6 is a detached view showing the side-switch wipers and contacts therefor.

In the present disclosure, the invention-is shown as. applied to'a switchof'the panel type, which may be similar to that disclosed in Craft and Reynolds Patent No; 1,123,696, although. any desired type of panel switch may be substituted for use with the present operating. mechanism.

InFig. 1, 1 indicates-a supporting shaft to which a brush. set 2 is secured. A- series )t',contacts 3 is provided :t'or the brushset. Secured to the shaft 1. at its lower end isan extension 4, which willhereinafter'be referred to as an elevating bar. The elevating bar 4 isprovided ,onone edgewith. a series of teeth 55, arranged for operative engagement with the .teeth .of5the gearrwheelr'fi mounted? on. a. shaft '7. -The* opposite edge;

of thei-bar ,is pro'vide'd with aseriesirof ratchetateeth 8 adapted-to be engaged by a stepping pawl E 9 and a. holding pawl :10. The .barqand shaft. Lare slidablyz. but;- nonnotatablylsupported-ein.any desiredlmanner.

Also rotatably mounted on the shaft 7 is an escape-wheel 11. The escape-wheel 11 and the gear-wheel 6 are connected by means of the coil spring 12, the outer end of which is secured to the gear-wheel 6, the inner end being secured to the escape-wheel 11. The spring brake-shoe 13 is secured at one end to the escape-wheel 11, and has the laterally extending stop portion 14 at the other end. This brake-shoe curves inwardly so as to lie eccentric to the shaft 7. Pivotally secured to the gear-wheel 6 is a brake member 15, which is normally held in engagement with the shaft 7 by means of a spring 16. Upon rotation of the gear-wheel 6 in an anti-clockwise direction with relation to the escape-wheel 11, the brake member 15 will be engaged with increasing force by the brake-shoe 13, and the gear-wheel will be stopped when it reaches a definite relative position to the escape-wheel. Due to the centrifugal action of the brake member 15, the force of the braking action increases as the speed of the wheel 6 increases. The parts are thus gradually brought to the stopping position and excessive jar is avoided.

The escape-wheel with the stop mechanism just described, is the light-setting stop member above referred to, and is arranged to be rotated in an anti-clockwise direction, as viewed in Fig. l, by means of the stepping members 17 and 18 located on opposite sides of the ratchet-wheel 11 and acting to produce a balanced movement of the Wheel. These stepping members have a common pivotal connection to the operating lever 19 by means of the rivet or pin 20. The sprin 21 tends to force the stepping members 1! and 18 into engagement with the ratchetwheel 11. The stepping members are, however, maintained retracted during certain operations of this portion of the switch by means of the cam member 22 when positioned between the rearwardly extending portions of the stepping members 17 and 18. The member 22 is carried by an arm pivotally mounted in any suitable manner in a clip 23 carried by the frame, and is provided with a spring 24, which tends to move the cam to an inoperative position. The member is provided at its rear end with an anti-friction roller 25 which is arranged to be operatively engaged by a cam surface on the shaft or change-over bar 26. The bar 26 is slidably mounted in the clips 27 and 28 and has a plurality of functions. It controls the operative position of the pawls 9 and 10 and of the cam 22. A spring 29, which has one end secured to the lower end of the bar 26 and the other end secured to a pin fixed to the switch frame, tends to move the bar in a downward direction, and the downward movement is controlled by the escape-Wheel 30 through the medium of.

the detent 31, which, in turn, is operated by the elcctromagnet A collar 33, mounted on the shaft 34, carries a ratchet wheel 35, arranged to be engaged by a. pawl 37 pivotally carried by a lever 36 fulcrumed on the shaft 34. The opposite end of the lever 36 is provided with an elongated slot 38, in which is positioned the pin 39 secured to the bar Fixed to the lever 36 are the wipers 39, 4,0, 11, 4-2, -13 and 1 1. These wipers and the contacts 45 arranged to be engaged thereby, are in the nature of an auxiliary or side switch, and the brushes 39 to 44 inclusive are moved one step with each energization of the magnet 32.

The ratchetwheel 11 s rotated by the forward and backward movement of the stepping members 17, 18 by means of the bar 19, which is pivotally mounted on the pin 46. The lever 19 is provided with an armature 47 of the stepping magnet 1-8. The lever 19 is provided at its upper end with an angular extension 19 to which is secured the stepping pawl 9. The spring 50, one end of which is secured to the arm 1-9 and the other to the upper portion of the pawl 9, tends to force said pawl into engagement with the ratchet teeth 8. The lower end of the pawl 9 is provided with an anti-friction roller 51, and is arranged to be engaged by the cam 52 on the shift bar 26 in order to cause said pawl to assume an inoperative position. The holding pawl 10 is pivotally supported on the fixed pin 53, and is provided with a spring 54-, which tends to move said pawl into engagement with the teeth 8. The lower end of the pawl member 10 is provided with an antifriction roller 55, which is arranged to be engaged by a cam 56 on the shift bar 26 in order to hold said pawl retracted.

The rod 1 is provided with an extension 57 which engages the lever 36 when the rod approaches its normal position on upward movement. On continued movement of the bar 1, the lever 36 moves the change-over bar 26 to bring an insulating stud 58 thereon into engagement with contact 59, forcing it upward to engage contact 60. The clo sure of these contacts may be employed to cut off the interrupter current for the magnet 48. The bar 4 will move slightly above normal position, and to drop it back a cam 61 is provided on the cam shaft 26 which, at its upper limit, disengages pawl 9 from the rack 8, allowing the pawl 10 to drop into the lowermost tooth of the rod 4. In this position the pawl 9 again engages the rod.

The ratchet wheelll carries in fixed rela tion to it a toothed wheel 64-, and mounted on a stud 65, secured to the switch frame, is a pawl 66 toothed at the end to engage said toothed wheel. A spring 67 tends to hold this pawl in engagement with said toothed w e i he-un asu i ce ef-thenetent 18 hasa e amrsur ace 68. on which a pin-v.69 :carried by the-pawl=;66-rides. ;In the .positiomshown; in j 1, the; pawl is. inactive, but :when the e"a m?.22 is; withdrawn, the stepping ,members v 171 and 18am drawn into engagement with-,the. ratchet wheel 11, and pawl 66 engages toothed wheel 64 to lock it so1-it-,will- ,not..be- .movedby; the. weight of the elevator rodgA, when it 1 is brought to *lfestby. the engagement of. member: 15 with .the brakeshoe =13. =On actuation of magnet 4&when thestepping membersl'? andv 18 are in. engagement with 5' the ratchet --wheel 11, .the detent l8cis, mowed-forward and pin '69 on pawl 66 rides up on cam 68.,ofstepping .member 18, thus. withdrawing the pawl and permitting actuation .of ratchet wheel 11 by said stepping membersmsbefore described. 'Qn.retracti.ve movement of said stepping member, the pawl 66 @will again engage with thegtoothedwheel 64 to prevent turther movement, thus preventing overthrow in a .downwarddirection.

When in its normal position, the switch isso positioned thatthebrushes areat the top of the terminalnbank instead of at the .bottom,-'as is.vusualwith switches of this type.

. .he device operates asfollows: When a switch is selected for; use, a single impulse is,sent through the magnet 32,-which operatesthe detent-3l.andpermits one step of theescapewheelfiO. 1 This movement causes thecams 52and 56 to engage the rollers 51 and respectively and retract the step pingpawl-Qmnd the holding pawl 10. It also permits the roller 25 to.-beforcedv into the notch 62 .and thusgremove the cam 22 .fnom'zbetween theprojecti-ng-ends of the stepping members17, and 18. A series of impulses is now sent through the magnet 48, causing a rapid reciprocating. movement of the stepping members 17- and 1 18. :With each forward movement, the point of. the stepping -memb.er-.-17- engages one-of the teethof the-ratchetawheel 11 andrevolves it slightly over half a step. ,This. permits the point of; stepping member 7 18 to. drop behind one .ofthe teethof the ratchet-wheel 1l,,.and upon theretraction of the-detents, due to. the ,.spring 63asecured to the lever 19.and,.apin on the'switch frame, the action is reversed, the ratchet-wheel -;being again advancedq} slightly. over half. a step. by the stepping member 18,. thus permitting the detent 17 to drop .behind the next tooth. In'thismanner, .the; .stop.-member is stepped around .until th e endsoftherseries of-impul es; wit th fir t p of th r tche ahe .lLithestep r1 -0n r1ak hc =,l is ma led cu ..;b ,ep ra i en agement w t theibrake-mem ml Ell bru h. supp inglsheftkbpginste mored w wrdly, du

to: thetension producedeinthe spring 12. 'Inethe usual. operation ofathe device, the stop member will be. moved more rapidly than. the switch will follow, and will; reach the set position beforethe brake member 15 again engages the stop14c. Should it be desireduto move. the brushes to a position :near the bottom of, the, terminal bank, the

switch shaft may: reach sufficient momentum to overtake the. stop member, but this will in no way, affect the stopping of. the device,

as. the brake 15 will immediately engage the shoe 14 and cause: the downward movement .ofthe shaft 1 to, be retarded. .YVhen,

however, the stop has moved toits set position, the brake'15 continues its movement along the brake-shoe 13-until it is brought into engagement with the stopll. At this time the brush set 2 will occupy a position below the last terminal in the group of terminals to which access is desired. Another impulse is now transmitted through the magnet .32, causing the change-over 'bar 26 to move downward another step. The cams 52 and 56 are now movedso as to occupy a position below the rollers 51 and 55, and

permit the pawls 9 and 10- to again engage -ment of thesideeswitch wipers may be accomplished by sending another impulse through magnet 32. .As the wipers::89 to 44 inclusive are'fixed to thelever 36, they will bemoved from one contact el5flto another upon each energization of the escape magnet 32.

xUponthe termination of the. conversation orwhen disconnection isdesired, a circuit will be completed. through the magnet 48 in series .with an interrupter, thus causing armature 47 to be repeatedly attracted and retracted, thus actuating the pawl 9 .to step up the switch until it reaches its normal or uppermost position, when the circuit through the magnet. 48 may. be broken by the contacts-59 and 60 or in any desired manner. The pawl 10 acts to prevent return movement ofthe bar 4. The bar 4: is'provided with, an extension'57 which engages the lever-'36 as the switch approaches its normal position 1 and returns; said lever to; the position shown in-Fig. 1, or itsnormalposition.

The lever 36 will in turn movet-he :.ba11;.2 6, carrying thescams 52; and 56 over their re- 52 and 56 are so made as to be deflected under spring tension so as to allow of their passing their respective rollers in upward movement of the bar 26, but to withdraw the pawls 9 and 10 in the downward movement. The elevator bar will have been raised slightly above normal position by this action, bringing the cam 61 on the bar 26 into contact with the roller 51 and dis engaging the pawl 9, whereupon the elevator bar at drops until the pawl 10 engages in the lowermost tooth thereo In the upward. movement of the lever arm 36, the pawl 37 will have passed over the next tooth on ratchet wheel 35, and on the bar 4 being reset from its overthrow position, will return, turning ratchet wheel 35 to bring Contact 40 into engagement with the first of contacts 15. The bar 26 will have been permitted to drop sufficiently to disengage stud 58 from contacts 59 and 60 which control the interrupter sending impulses to magnet 48 at completion of conversation, and to disengage the cam 61 from roller 51.

In moving back to normal, the pawls 9 and 10' are continuously actuated, while the stepping members 17 and 18 are also actuated for the very brief interval while the roller 25 is passing the notch 62. This actuation of the stepping members, however, is without eifect on the return operation of the switch, as should the stepping members engage the ratchet-wheel 11, the spring 12 will only be wound slightly and will be released after the notch 62 is passed and the stepping members disengaged. The pawls 9 and 10 prevent downward movement under such conditions. The tension of the spring 12 will then return the ratchet-wheel 11 to its normal position relative to the wheel 6.

That is claimed is:

1. In an electrically operated switch, av movable contact, a support therefor, groups of stationary contacts engaged by said movable contact, means for moving said support, means for stopping said support when said movable contact has reached the desired group, means to move said support Jo the desired contact in said group, means to return said support to its normal position, and common operating means to actuate all of said means.

2. In an electrically operated switch, a movable contact, a support therefor, groups of stationary contacts engaged by said movable contact, means for moving said support, means for stopping said support when said movable contact has reached the desired group, means to move said movable contact to the desired contact in said group, means to return said support to its normal position and a common electro-magnet for operating said means.

3. In an electrically operated switch, an

auxiliaryrotatable switch, a movable brush" supporting bar, electromagnetic means to rotate said auxiliary switch out of normal position, means mechanically controlled thereby to release said bar, means to restore said bar to normal position, and means controlled by return movement of said bar to rotate said auxiliary switch to normal position.

4. In an electrically operated switch, an auxiliary switch, a movable brush-supporting member, mechanism to actuate said member, and a bar actuated by said auxiliary switch to control the operation of said mechanism, said bar being reset to normal position by said auxiliary switch on its return to normal.

5. In an electrically operated switch, a movable brush-supporting member, an auxiliary switch, means normally engaging said member to hold it in normal position, means to move said member toward said position when it is out of normal, and means mechanically actuated by said auxiliary switch to disengage said engaging means from said member to release said member, said disengaging means being reset to normal position by said auxiliary switch.

6. In an electrically operated switch, a movable brush-supporting member, an auxiliary switch, a bar operated on movement of said auxiliary switch, means controlled by said shaft to release said member, means to return said member to normal position, and means whereby said auxiliary switch is reset to normal position by the return of said member to normal.

7. In an electrically operated switch, switch contacts therefor, a movable toothed brush-supporting member governing engagement of said contacts, an actuating pawl normally engaging said member, a holding pawl for engaging said member, a bar having cams to engage said pawls, means to operate said bar to move said cams to withdraw said pawls to release said member, means to move said member on its release,

and means to move said actuating pawl to step said member.

8. In an electrically operated switch, switch contacts therefor, a movable toothed brush-supporting bar governing engage ment of said contacts, an actuating pawl normally engaging said bar, a holding pawl for engaging said bar, a cam shaft having cams to engage said pawls, a mechanism to operate said shaft to cause said cams to withdraw said pawls to release said bar in one position and to move other of said cams to release said actuating pawl in another position, means to move said bar on its release, means to move said actuating pawl to step said bar, means on said bar to move said mechanism to position said shaft so other of said cams release said actuating pawl, thereby permitting said bar to move back a step, and means controlled by said back movement to reset said mechanism to normal position 9. In an electrically operated switch, a movable contact, a support therefor, a stop for determining the stopping position of said support, a ratchet wheel to move said stop, a stepping member to operate said ratchet wheel, means to control engagement of said stepping member with said ratchet wheel, and locking means controlled by said stepping member to lock said stop means against movement.

10. In an electrically operated switch, a movable contact, a support therefor, a stop for determining the stopping position of said support, a ratchet wheel to move said stop, a stepping member to operate said ratchet wheel, cam means on said stepping member, a locking pawl operated by said cam, and means movable with said stop to be engaged by said pawl to prevent movement of said stop 11. In an electrically operated switch, a movable contact, a support therefor, a stop for determining the stopping position of said support, a ratchet wheel to move said stop, a stepping member to operate said ratchet wheel, a locking pawl, a locking wheel movable with said stop arranged to be engaged by said pawl, and cam means on said stepping member normally holding said Dawl in non-engaging position.

12. In an electrically operated switch, brushes, supporting means for said brushes, stop means for determining the stopping position of said supporting means, rotatable means connecting said bar to said stop means, and a brake between said stop and rotatable means.

13. In an electrically operated switch, brushes, supporting means for said brushes, stop means for determining the stopping position of said supporting means, rotatable means connecting said supporting means to said stop means, a brake shoe on said stop means, and a brake member eccentrically mounted on said rotatable means to engage said shoe.

14. In an electrically operated switch, brushes, a movable brush-supporting means, a stop means for determining the stopping position of said supporting means, a ratchet wheel to move said stop means, and reciprocating pawl means operable to turn said wheel on movement in both directions.

15. In an electrically operated switch,

brushes, a movable brush-supporting means, a stop means for determining the stopping position of said supporting means, a ratchet wheel to move said stop means, and means to operate said wheel comprising reciprocating pawls, one operatively engaging said wheel on one side when the pawls move in one ,direction, and another pawl operatively engaging said wheel on the opposite side on movement of the pawls in the other direction.

16. In an electrically operated switch, a contact, a movable support therefor, a mechanical stop for determining the stopping position of said support, means to move said support at high speed until said stop is encountered, and means to move said support at slow speed subsequent to said encounter.

17. In an electrically operated switch, a plurality of groups of contacts, movable contacts for association with any of said contacts, a movable support for said movable contact, a mechanical stop for determining the group to which said support is to move, means for moving said support at high speed until said stop is encountered, and means to move said support at slow speed subsequent to said encounter to associate the movable contact with a desired contact in the selected group.

18. An automatic selective switch having a movable terminal member, a multi-position auxiliary switch for controlling the operating circuits of said member, and means carried by said auxiliary switch for mechanically controlling the movement of Said member.

19. An automatic selective switch having a movable terminal carrying member, mechanical means cooperating with said member for determining the movement thereof, a multi-position movable circuit controlling element, and means carried by said element for directly controlling said mechanical means.

20. An automatic selective switch, fixed circuit terminals, brushes cooperating therewith, means for actuating said brushes, a multi-position auxiliary switch for controlling the operating circuits of said automatic switch, and means carried by said auxiliary switch for mechanically controlling said actuating means.

In witness whereof, I hereunto subscribe my name this 9th day of June, A. D., 1916.

MAURICE K. MoGrRATH.

Copies oi this patent may be obtained for five cents each. by addressing the Commissioner of Patents,

Washington, D. G. 

